Use of mobile (pronounced "moh bile" in Oz) phones while driving in Oz is currrently illegal unless you're using a 'hands-free" system. Even then, the research indicates that using one while driving has the same detrimental effect on driving-reaction time as a blood-alcohol level of 0.05, the (upper) legal limit for drivers in Oz. They don't work where I live and in most of the places where I drive and one of the delights of fieldwork is the ability to legitimately be out of reach of unwanted communications.
The only ringtones I'd be interested in is one with my daughters saying, in unison, "Dad, answer the phone!" for when they're trying to contact me, and another with the call of the banjo frog (Limnodynastes dorsalis) which calls with a deep (and deeply satisfying), one-note call, "Bonk!"